The present invention relates generally to an apparatus for laying turf and, in particular, to an apparatus for laying large rolls of turf to produce a lawn.
Historically, turf (also commonly called sod) has been grown in nurseries, fields, and the like and has been cut into long rectangular strips for transportation to the desired location. The cut strips of turf are up to six feet long and weigh between forty and fifty pounds. After cutting, the turf is typically stored and transported on pallets either in flat strips or small rolls.
The laying of turf is generally very labor intensive and inefficient. The heavy rolls or strips of turf are lifted from a pallet by hand to the desired location. The turf is then unrolled and laid as closely as possible against the edge of the previously laid turf. The task of rolling, carrying, positioning, and unrolling strips of turf is time consuming, burdensome, and expensive.
There are numerous difficulties involved in laying turf by machine. Turf is an extremely difficult material with which to work, because it is heavy and yet has very little tensile strength. The tensile strength of the turf can also very greatly from one sample to another depending on the condition of the turf, such as its thickness, age, type of soil, moisture content, and variety of grass. Even within a single roll of turf, the characteristics of the turf can vary greatly because the top of the roll tends to dry out at a faster rate than the bottom portion of the roll. The turf also tends to stretch unevenly when it is being laid, forming unsightly buckles which must be removed. The turf may frequently break, interrupting the turf laying operation.
In recent years, turf harvesting machines have been developed to harvest rolls of turf up to forty-eight inches wide and over one hundred feet long. The use of such large rolls offers many potential benefits to both the turf layer and user. The user benefits from longer, wider turf with fewer seams, which in turn means less shrinkage, fewer weeds and crab grass, less curl, and a more acceptable appearance.
Cutting large rolls of turf and rolling them by machine also is efficient and economical. The amount of time and labor to initially cut and roll the turf is significantly reduced through the use of large rolls. Because of the size and weight of the turf harvested in large rolls, which often weigh over one thousand pounds, the large turf rolls must also be laid by machine.
As noted above, the turf is very difficult to work with and requires an accurate and reliable apparatus for laying the large turf rolls. The turf industry has a need for a new turf laying machine that is relatively small and maneuverable and able to lay the fragile turf accurately while reducing the likelihood of breaks and buckles in the turf when unwinding the roll.